What is the nursing management for antifreeze (ethylene glycol) ingestion?

Nursing Management for Ethylene Glycol (Antifreeze) Ingestion

Immediate nursing management for ethylene glycol ingestion should focus on rapid identification, administration of antidotes, preparation for hemodialysis, and close monitoring of acid-base status and renal function to prevent mortality and long-term morbidity.

Initial Assessment and Recognition

• Identify clinical presentation:

  • Early stage (30 min-12 hrs): Inebriation, ataxia, slurred speech, nausea/vomiting
  • Intermediate stage (12-24 hrs): Tachypnea, tachycardia, hypertension, pulmonary edema
  • Late stage (24-72 hrs): Flank pain, acute kidney injury, calcium oxalate crystalluria

• Obtain critical history:

  • Timing of ingestion (critical for treatment decisions)
  • Quantity ingested
  • Presence of co-ingestions, especially alcohol
  • Access to antifreeze or other ethylene glycol-containing products

Immediate Interventions

1. Secure airway, breathing, and circulation

   • Intubation may be necessary if decreased level of consciousness
   • IV access with two large-bore catheters

2. Laboratory monitoring:

   • Obtain STAT labs:
     • Ethylene glycol levels (if available)
     • Arterial blood gases
     • Electrolytes, BUN, creatinine
     • Anion gap and osmolal gap calculation
     • Calcium levels
     • Urinalysis (look for calcium oxalate crystals)

3. Administer antidotes (as ordered):

   • Fomepizole (preferred): Inhibits alcohol dehydrogenase to prevent toxic metabolite formation 1
   • Ethanol (alternative): If fomepizole unavailable

4. Prepare for hemodialysis:

   • Hemodialysis is strongly recommended for:
     • Severe metabolic acidosis (anion gap >27 mmol/L)
     • Ethylene glycol concentration >50 mmol/L
     • Presence of severe clinical features (coma, seizures, AKI) 2

5. Correct metabolic acidosis:

   • Administer sodium bicarbonate as ordered to maintain pH >7.2

Ongoing Monitoring and Management

1. Continuous cardiac monitoring:

   • Watch for arrhythmias from electrolyte disturbances and acidosis

2. Fluid management:

   • Maintain adequate hydration to support renal perfusion
   • Monitor fluid balance hourly
   • Assess for signs of pulmonary edema

3. Neurological assessment:

   • Frequent neurological checks (every 1-2 hours)
   • Document GCS score
   • Monitor for seizure activity

4. Renal function monitoring:

   • Strict intake and output measurement
   • Monitor urine output hourly (goal >0.5-1 mL/kg/hr)
   • Serial creatinine measurements

5. Antidote administration considerations:

   • During hemodialysis: Increase dosage of antidotes (fomepizole or ethanol) as they are dialyzable 2
   • Continue antidotes until ethylene glycol levels <20 mg/dL

Hemodialysis Management

• Prepare patient for hemodialysis when indicated:

  • Intermittent hemodialysis is preferred over other extracorporeal treatments 2
  • If intermittent hemodialysis unavailable, continuous kidney replacement therapy (CKRT) is recommended

• Monitor during hemodialysis:

  • Vital signs every 15-30 minutes
  • Blood glucose levels (especially if on ethanol therapy)
  • Signs of disequilibrium syndrome
  • Electrolyte imbalances

• Continue hemodialysis until:

  • Anion gap <18 mmol/L or
  • Ethylene glycol concentration <4 mmol/L 2

Special Considerations

• Alcohol withdrawal: Monitor for signs in patients with alcohol use disorder 2

• Pregnancy: Lower threshold for hemodialysis may be appropriate to reduce exposure to antidotes 2

• Repeated ingestion: Even patients with multiple previous ethylene glycol poisonings can recover with proper treatment 3

Critical Pitfalls to Avoid

1. Delayed recognition: Even small amounts of ethylene glycol can cause severe renal damage 4, 5

2. Inadequate antidote dosing during hemodialysis: Both fomepizole and ethanol are dialyzable and require increased dosing during ECTR 2

3. Premature discontinuation of hemodialysis: Continue until anion gap normalizes (<18 mmol/L) 2

4. Overlooking metabolite toxicity: Glycolate and oxalate are responsible for most toxic effects, not ethylene glycol itself 2, 5

5. Relying solely on ethylene glycol levels: Renal injury correlates better with glycolate levels than with ethylene glycol concentration 1

6. Missing co-ingestions: Other toxic alcohols or substances may be present

7. Inadequate monitoring of acid-base status: Metabolic acidosis may worsen despite treatment and require additional interventions